661 Oil Test 32:1 vs 40:1 vs 50:1 ?

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Whitespider
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...more importantly the fuel portion of the fuel/oil mix evaporates once it enters the motor depositing the oil. In other words, oil alone lubricates your motor,not fuel/oil mix.
So would most solvents in the oil (maybe not all)... so, in effect, the oil lubricating the engine would not be exactly the same as what gets poured from the bottle.
Most of those "solvents" are chemical components of gasoline.
 
Gypo Logger

Gypo Logger

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Now you tell me ..........







Now will you tell me what this means ? ........emulsifiable




These big werds too early before coffee is consumed .
Emulsification is the ability of two components to mix together such as oil and water. So as long as your mix has an emulsifier you will never get scoring due to moisture.
It's very similar to the tackifier in your bar lube.
 
Trx250r180

Trx250r180

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Emulsification is the ability of two components to mix together such as oil and water. So as long as your mix has an emulsifier you will never get scoring due to moisture.
It's very similar to the tackifier in your bar lube.
Thank you ,very nice explanation ,hope i am not the only one that learns from this .
 
Gypo Logger

Gypo Logger

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Thank you ,very nice explanation ,hope i am not the only one that learns from this .
Yes, when buying mix at your Stihl/Husky dealer it's important to ask them if the mix has an emulsifier because they often sub out the mix production off shore to the lowest bidder which has no emulsification. So buyer beware.
 
Ron660

Ron660

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I've run a bunch of oil in saws. Itasca from the gas station, stihl orange bottle, tsc, husky semi synthetic, ultra, all the klotz offerings, h1r, k2, 927, 710, and 800. I've not had any oil failures.
That's my question. Has anyone ever experienced an engine failure (low end..top end) due to a certain brand of 2-cycle oil mixed 40:1 or richer?
 
Whitespider
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That's my question. Has anyone ever experienced an engine failure (low end..top end) due to a certain brand of 2-cycle oil mixed 40:1 or richer?
In what time period??
I remember in the early 70s many two-cycles used a 16:1 mix, and engine failures were quite common... if I remember correctly, dad's first Arctic Cat snowmobile used "Purple Power" two-cycle oil mixed 24:1 and the crank failed.
My grandfather had an old outboard motor from the late 50s/early 60s that used 30w non-detergent motor oil mixed at 16:1 (I believe)... he'd fill the tank with gas, dump some motor oil in using the 'guess 'n' b'gosh" method, shake it a bit, and pull the rope. We had an old Montgomery-Wards washing machine motor up at the lake home that used the same 30w mixed 8:1 (but we also used the 'guess 'n' b'gosh" method of mixing)... it smoked something horrible and eventually the rod bearing failed.
*
 
Whitespider
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That's not always true or even often true. Some oils have toluene as a diluent and actually raise octane.
L-O-L Hardly.
You're trying to tell me that a few drops of toluene (at 114 octane) is enough to raise the octane number of oil (something with an octane number around 30-35) above the gasoline octane number... at best, it would only raise the oil octane a few points, still putting it way below gasoline.
*
 
bwalker
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L-O-L Hardly.
You're trying to tell me that a few drops of toluene (at 114 octane) is enough to raise the octane number of oil (something with an octane number around 30-35) above the gasoline octane number... at best, it would only raise the oil octane a few points, still putting it way below gasoline.
*
I am saying you can't say for certainty that oil reduces octane..
And where did you get the 35 octane nunber?
Good oils do not lower octane.
 
Whitespider
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I am saying you can't say for certainty that oil reduces octane..
And where did you get the 35 octane nunber?
Good oils do not lower octane.
(shrug) Prove me wrong then... that's a challenge.

But let me give you my argument first...
Octane and cetane numbers closely corresponded to the carbon chains in the fuel... shorter carbon chains, higher octane (lower cetane)... longer carbon chains, lower octane (higher cetane).
When crude oil is distilled the different chemicals are separated, each with it's own carbon chain. The distillates used in gasoline are relatively high in octane... and the octane number lowers as you work down from there. Diesel fuel is lower in octane (but higher in cetane) than gasoline... the octane number for diesel fuel works out to maybe around 40 maximum (and that would be some damn low quality diesel). Good quality diesel fuel with a high cetane number would have a octane number well below 30. The distillates used for lubricating oils are some distance below those used for diesel fuel... my statement giving lubricating oil an octane rating of 30-35 is damn generous, and likely way too high.

And as you research, you'll find the the octane number (and carbon chain) of synthetic oils are near identical to dino oil.
Adding oil to gasoline results in a (slightly) lower octane number... the more oil you add, the lower the resulting octane number... it-is-what-it-is.

refine.jpg
 
bwalker
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(shrug) Prove me wrong then... that's a challenge.

But let me give you my argument first...
Octane and cetane numbers closely corresponded to the carbon chains in the fuel... shorter carbon chains, higher octane (lower cetane)... longer carbon chains, lower octane (higher cetane).
When crude oil is distilled the different chemicals are separated, each with it's own carbon chain. The distillates used in gasoline are relatively high in octane... and the octane number lowers as you work down from there. Diesel fuel is lower in octane (but higher in cetane) than gasoline... the octane number for diesel fuel works out to maybe around 40 maximum (and that would be some damn low quality diesel). Good quality diesel fuel with a high cetane number would have a octane number well below 30. The distillates used for lubricating oils are some distance below those used for diesel fuel... my statement giving lubricating oil an octane rating of 30-35 is damn generous, and likely way too high.

And as you research, you'll find the the octane number (and carbon chain) of synthetic oils are near identical to dino oil.
Adding oil to gasoline results in a (slightly) lower octane number... the more oil you add, the lower the resulting octane number... it-is-what-it-is.

View attachment 423042
The thing your not considering is that most of the oil isnt in the fuel vapor/air charge. Its on the surfaces of the piston, head etc. So, its effects on combustion are different. And we are talking about a ver small percentage of oil in the fuel anyways.
And octane isnt measured by carbon chains. Its measured by a test engine..
 
SCHallenger
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Octane is an 8 carbon chain. Any carbon chain, shorter or longer, is an organic compound other than octane. As you start with 1 carbon & 4 hydrogens, you have methane, 2 carbons & 7 hydrogens is ethane, & so on up the length of the chain (propane, butane, pentane,etc. until you reach the 8 carbon 18 hydrogen configuration which is octane. Octane levels are determined by the percentage of octane in the fuel. 100% octane would be pure fuel. The "octane rating" can be raised by adding compounds such as tetraethyl lead, or lowered by dilution with other additives.
 
bwalker
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Octane is an 8 carbon chain. Any carbon chain, shorter or longer, is an organic compound other than octane. As you start with 1 carbon & 4 hydrogens, you have methane, 2 carbons & 7 hydrogens is ethane, & so on up the length of the chain (propane, butane, pentane,etc. until you reach the 8 carbon 18 hydrogen configuration which is octane. Octane levels are determined by the percentage of octane in the fuel. 100% octane would be pure fuel. The "octane rating" can be raised by adding compounds such as tetraethyl lead, or lowered by dilution with other additives.
As measured by the R+M/2 method..
 

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